Current automotive head-up displays (HUDs) enable the driver to view vehicle operational information, such as vehicle speed and/or navigation directions. The head-up display apparatus typically comprises a mirror assembly to produce a virtual image on a combiner. The virtual image can only be viewed by a user when their eyes are located within a virtual three-dimensional space referred to as an eyebox (or head position box). The free form (imaging) mirror corrects image error from the combiner and is configured such that the eyebox is positioned to enable the driver to view the virtual image when in a normal driving position. Due to packaging requirements in a vehicle, the size of the imaging mirror is limited and the eyebox is not accessible to a passenger in the vehicle under normal operating conditions. Thus, the passenger is unable to view the virtual image produced by the head-up display apparatus.
It is against this background that the present invention has been conceived. At least in certain embodiments, the present invention seeks to overcome or ameliorate at least some of the shortcomings associated with known head-up display apparatus.